/**
 * Copyright 2014 Eediom Inc.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.araqne.logdb.metadata;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.nio.charset.Charset;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.atomic.AtomicLong;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.felix.ipojo.annotations.Component;
import org.apache.felix.ipojo.annotations.Invalidate;
import org.apache.felix.ipojo.annotations.Requires;
import org.apache.felix.ipojo.annotations.Validate;
import org.araqne.log.api.Log;
import org.araqne.log.api.LogPipe;
import org.araqne.log.api.Logger;
import org.araqne.log.api.MultilineLogExtractor;
import org.araqne.logdb.AccountService;
import org.araqne.logdb.MetadataCallback;
import org.araqne.logdb.MetadataProvider;
import org.araqne.logdb.MetadataService;
import org.araqne.logdb.QueryContext;
import org.araqne.logdb.QueryParseException;
import org.araqne.logdb.Row;

@Component(name = "logdb-log-metadata")
public class LogMetadataProvider implements MetadataProvider {
	@Requires
	private AccountService accountService;

	@Requires
	private MetadataService metadataService;

	@Validate
	public void start() {
		metadataService.addProvider(this);
	}

	@Invalidate
	public void stop() {
		if (metadataService != null)
			metadataService.removeProvider(this);
	}

	@Override
	public String getType() {
		return "logs";
	}

	@Override
	public void verify(QueryContext context, String queryString) {
		if (!context.getSession().isAdmin()){
		//	throw new QueryParseException("no-read-permission", -1);
			throw new QueryParseException("95020", -1, -1, null);
		}
	}

	@Override
	public void query(QueryContext context, String queryString, MetadataCallback callback) {
		File dir = new File(System.getProperty("araqne.log.dir"));

		List<File> files = new ArrayList<File>();
		for (File f : dir.listFiles()) {
			if (f.getName().startsWith("araqne.log") && !f.getName().equals("araqne.log"))
				files.add(f);
		}

		Collections.sort(files);

		RowPipe pipe = new RowPipe(callback);

		// rolled files
		for (File f : files) {
			loadFile(pipe, f);
		}

		// today log file
		loadFile(pipe, new File(dir, "araqne.log"));
	}

	private void loadFile(RowPipe pipe, File f) {
		FileInputStream is = null;
		try {
			is = new FileInputStream(f);
			MultilineLogExtractor extractor = new MultilineLogExtractor(null, pipe);
			extractor.setBeginMatcher(Pattern.compile("^\\[\\d{4}-\\d{2}-\\d{2} \\d{2}:\\d{2}:\\d{2},\\d{3}\\]").matcher(""));
			extractor.setDateMatcher(Pattern.compile("\\[(.*)\\]").matcher(""));
			extractor.setDateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss,SSS"));
			extractor.setCharset(Charset.defaultCharset().name());
			extractor.extract(is, new AtomicLong());
		} catch (IOException e) {
		} finally {
			if (is != null) {
				try {
					is.close();
				} catch (IOException e) {
				}
			}
		}
	}

	private static class RowPipe implements LogPipe {
		private Matcher matcher;
		private MetadataCallback output;

		public RowPipe(MetadataCallback output) {
			this.output = output;

			matcher = Pattern.compile("(?sm)\\[.*?\\]\\s+(\\S+) \\((\\S+)\\) - (.*)").matcher("");
		}

		@Override
		public void onLog(Logger logger, Log log) {
			Row row = buildRow(log);
			output.onPush(row);
		}

		@Override
		public void onLogBatch(Logger logger, Log[] logs) {
			for (Log log : logs) {
				if (log == null)
					continue;

				Row row = buildRow(log);
				output.onPush(row);
			}
		}

		private Row buildRow(Log log) {
			String line = (String) log.getParams().get("line");
			Row row = new Row();
			row.put("_time", log.getDate());

			if (line != null) {
				matcher.reset(line);
				if (matcher.matches()) {
					row.put("level", matcher.group(1));
					row.put("class", matcher.group(2));
					row.put("msg", matcher.group(3));
				} else {
					row.put("line", line);
				}
			}

			return row;
		}
	}
}